Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-12-01T00:49:28.775Z Has data issue: false hasContentIssue false
  • English
  • Français

Effect of multiple reflows on mechanical strength of the interface formed between Sn–Zn–Bi solder and Au/Ni/Cu bond pad

Published online by Cambridge University Press:  03 March 2011

Ahmed Sharif ,
Y.C. Chan  and
H.W. Zhong
Ahmed Sharif
Affiliation:
Department of Electronic Engineering, City University of Hong Kong, Kowloon Tong, Hong Kong
Y.C. Chan*
Affiliation:
Department of Electronic Engineering, City University of Hong Kong, Kowloon Tong, Hong Kong
H.W. Zhong
Affiliation:
Department of Electronic Engineering, City University of Hong Kong, Kowloon Tong, Hong Kong
*
a) Address all correspondence to this author. e-mail: [email protected]
Get access

Abstract

In this work, the shear strengths and interfacial reactions of Sn–8Zn–3Bi and Sn–8Zn–1Bi (wt%) solders with Au/Ni/Cu ball grid array (BGA) pad metallization were systematically investigated after multiple reflows. The peak reflow temperature was fixed at 230 °C. After the shear test, fracture surfaces were investigated using a scanning electron microscope equipped with an energy dispersive x-ray spectrometer. Cross-sectional studies of the interfaces were also conducted to correlate with the fracture surfaces. Two failure modes, ball cut and pad lift, were assessed for the different solders and reflow cycles. It was found that the shearing forces of both the Sn–Zn–Bi solder joints tended to increase slightly with an increase in the number of reflow cycles due to augmentation of the shearing area. A layer-type spalling of the interfacial intermetallic compounds (IMCs) was observed very early in the liquid-state reaction for the solder alloys. The active nature of the Zn confirmed an instant reaction zone at the interface to maintain the bonding between the solder and the substrate.

Keywords

CompoundSolderingStrength
Type
Articles
Information
Journal of Materials Research , Volume 22 , Issue 1 , January 2007 , pp. 40 - 45
Copyright
Copyright © Materials Research Society 2007

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1Suganuma, K.: Preface-special issue on lead-free soldering in electronics. Mater. Trans. 45, 605 (2004).Google Scholar
2Zeng, K. and Tu, K.N.: Six cases of reliability study of Pb-free solder joints in electronic packaging technology. Mater. Sci. Eng. R 38, 55 (2002).CrossRefGoogle Scholar
3Abtew, M. and Selvaduray, G.: Lead-free solders in microelectronics. Mater. Sci. Eng. R 27, 95 (2000).CrossRefGoogle Scholar
4Kim, K.S., Yang, J.M., Yu, C.H., Jung, I.O., and Kim, H.H.: Analysis on interfacial reactions between Sn–Zn solders and the Au/Ni electrolytic-plated Cu pad. J. Alloys Compd. 379, 314 (2004).CrossRefGoogle Scholar
5Glazer, J.: Microstructure and mechanical-properties of Pb-free solder alloys for low-cost electronic assembly—A review. J. Electron. Mater. 23, 693 (1994).CrossRefGoogle Scholar
6Knott, S. and Mikula, A.: Thermodynamic properties of liquid Al– Sn–Zn alloys: A possible new lead-free solder material. Mater. Trans. 43, 1868 (2002).CrossRefGoogle Scholar
7Iwasaki, T., Kim, J.H., Mizuhashi, S., and Satoh, M.: Encapsulation of lead-free Sn/Zn/Bi solder alloy particles by coating with wax powder for improving oxidation resistance. J. Electron. Mater. 34, 647 (2005).CrossRefGoogle Scholar
8Shih, P.C. and Lin, K.L.: Interfacial bonding behavior with introduction of Sn–Zn–Bi paste to Sn–Ag–Cu ball grid array package during multiple reflows. J. Mater. Res. 20, 219 (2005).CrossRefGoogle Scholar
9Kim, Y.S., Kim, K.S., Hwang, C.W., and Suganuma, K.: Effect of composition and cooling rate on microstructure and tensile properties of Sn–Zn–Bi alloys. J. Alloys Compd. 352, 237 (2003).CrossRefGoogle Scholar
10Shohji, I., Nakamura, T., Mori, F., and Fujiuchi, S.: Interface reaction and mechanical properties of lead-free Sn–Zn alloy/Cu joints. Mater. Trans. 43, 1797 (2002).CrossRefGoogle Scholar
11Shohji, I., Gagg, C., and Plumbridge, W.J.: Creep properties of Sn–8mass% Zn–3mass% Bi lead-free alloy. J. Electron. Mater. 33, 923 (2004).CrossRefGoogle Scholar
12Kim, K.S., Ryu, K.W., Yu, C.H., and Kim, J.M.: The formation and growth of intermetallic compounds and shear strength at Sn–Zn solder/Au–Ni–Cu interfaces. Microelectron. Reliab. 45, 647 (2005).CrossRefGoogle Scholar
13Sharif, A. and Chan, Y.C.: Interfacial reactions of Sn–3.5% Ag and Sn–3.5% Ag–0.5% Cu Solder with electroless Ni/Au metallization during multiple reflow cycles. J. Mater. Sci.-Mater. Electron. 16, 153 (2005).CrossRefGoogle Scholar
14Li, M., Lee, K.Y., Olsen, D.R., Chen, W.T., Tan, B.T.C., and Mhaisalkar, S.: Microstructure, joint strength and failure mechanisms of SnPb and lead-free solders in BGA packages. IEEE Trans. Electron. Pack. 25, 185 (2002).Google Scholar
15Koo, J.M. and Jung, S.B.: Effect of substrate metallization on mechanical properties of Sn–3.5Ag BGA solder joints with multiple reflows. Microelectron. Eng. 82, 569 (2005).CrossRefGoogle Scholar
16Hsiao, L.Y. and Duh, J.G.: Characterizing metallurgical reaction of Sn–Pb solder with Ni/Cu under-bump metallization by electron microscopy. Thin Solid Films 469–470, 366 (2004).CrossRefGoogle Scholar
17Nurmi, S.T., Sundelin, J.J., Ristolainen, E.O., and Lepisto, T.: The influence of multiple reflow cycles on solder joint voids for lead-free PBGAs. Solder. Surf. Mount. Technol. 15, 31 (2003).CrossRefGoogle Scholar
18Islam, M.N., Chan, Y.C., Sharif, A., and Alam, M.O.: Comparative study of the dissolution kinetics of electrolytic ni and electroless Ni–P by the molten Sn3.5Ag0.5Cu solder alloy. Microelectron. Reliab. 43, 2031 (2003).CrossRefGoogle Scholar